1. Field of the Invention
The present invention relates to a VCA-based lens driving device, and more particularly, to a lens driving device with auto-focusing and optical image stabilization mechanisms.
2. Description of the Prior Art
Conventionally, Hall sensor is used to sense movement of auto-focusing magnets (AF magnets) and optical image stabilization magnets (OIS magnets) in a photographing lens assembly with a VCA (Voice-Coil-Actuator) based lens driving device. The movement of the AF magnets and OIS magnets may be caused by a user's hand shaking during an image-capturing process. FIG. 11 shows a partial configuration of AF/OIS common magnets and OIS coils in a conventional VCA-based lens driving device, in which an X-axis OIS coil 9x is placed below a AF/OIS common magnet 6x. A Hall sensor 10x can be placed below a center hollow of the X-axis OIS coil 9x to save space. The Hall sensor 10x can sense the magnetic signal due to the movement of the magnet atop. However, the electromagnetic field of the OIS coil 9x also influences the Hall sensor 10x to cause erroneous magnet signal for the magnet movement.
Therefore, it is desirable to provide a solution to reduce the impact of the magnet field of the OIS coil on the Hall sensor.